超稠油老区氮气辅助VHSD开发数值模拟  

Numerical Simulation of Nitrogen-Assisted VHSD Development in Old Super-Heavy Oil Reservoirs

作　　者：王攀[1] 刘洋[1] 梁向进[1] 郑爱萍[1] 秦凝涵 冯志军[1] WANG Pan;LIU Yang;LIANG Xiangjin;ZHENG Aiping;QIN Ninghan;FENG Zhijun(PetroChina Xinjiang Oilfield Company,Karamay 834000,Xinjiang,China)

机构地区：[1]中国石油新疆油田分公司,新疆克拉玛依834000

出　　处：《新疆石油天然气》2024年第1期38-43,共6页Xinjiang Oil & Gas

基　　金：国家科技重大专项“油田开发新技术新方法研究”(2021DJ0901)。

摘　　要：转直井辅助水平井重力泄油(VHSD)开发方式已成为超稠油老区进一步提高区块采油速度、油藏采收率的重要调整手段。氮气辅助VHSD的增能提压、顶部隔热效应可有效解决超稠油老区吞吐后压力保持程度低、驱泄操作压力低、蒸汽腔温度低的问题,进而实现节约蒸汽用量、提高产油水平、提升油汽比和减耗降碳的目的。以克拉玛依油田九区某VHSD开发单元为例,采用数值模拟方法分析了在氮气辅助VHSD开发过程中注氮时机、注氮方式、注氮量等参数对提压增能、建立隔热层的影响,以及采出速度和累计注采的变化特点。研究表明,转驱泄初期采用段塞方式注入氮气可有效建立隔热层;矿场试验表明,井组油汽比提升0.025,日产油提升0.7 t,取得了较好的应用效果。研究成果为同类型超稠油老区氮气辅助VHSD效益开发提供了技术借鉴。Changing over to Vertical-Horizonal well Steam Drive(VHSD)development pattern is becoming an important means for improving block production rate and recovery rate in old super-heavy oil reservoirs.Nitrogen-assisted VHSD can increase energy and pressure and form a heat insulating top layer,effectively solving the problems of pressure maintenance,low displacement pressure,and low steam chamber temperatures following huff-puff operations in old heavy oil reservoirs,saving steam volume,improving oil produc-tion levels and oil-steam ratio,and reducing carbon consumption.This paper examines a VHSD development unit in the Ninth Block of Karamay Oilfield.Numerical simulation is used to determine the influences of different parameters(nitrogen injection timing,injection pattern,injection amount)on pressure and energy increase,and on the establishment of heat insulating layers.Variations in recovery rates and accumulated injection-production indicators during VHSD development are also analyzed.The results show that nitrogen in-jection by slug can help to build a heat insulating layer in the initial stages of the transition to displacement and drainage.In field tests of this nitrogen-assisted VHSD approach,the oil-steam ratio of the study well group was increased by 0.025,and daily oil production was increased by 0.7 t,which are favorable results.This study provides a technical reference for efficient development using nitrogen-assisted VHSD in similar old heavy oil reservoirs.

关 键 词：VHSD 氮气辅助 增能提压 隔热层 数值模拟 超稠油 

分 类 号：TE345[石油与天然气工程—油气田开发工程]